A cannabis factory was discoved by Police at the weekend inside a property on Griston Road, Watton. Picture: Ian Burt

But inside the five-bedroom house and behind its green front door and net curtains, police uncovered a large-scale cannabis factory, including lights, fans and air ducts.

Offices found more than 500 plants at the three-storey property on Griston Road, in Watton, at around 8pm on Friday evening,

Neighbours reported several police cars and vans on the road, and some said they saw items being carried out of the property by police.

One neighbour, Janice Johnstone, described the area as having a strong community feel, and said she didn’t see anyone in the property coming and going.

She said: “You read about it in the paper, and hear about it on the TV, but it doesn’t happen to you.”

Others said they saw the police arriving but said they saw or knew little of who rented the property

A 34-year-old man, Arjan Difhema, was taken to Wymondham police station for questioning about the cannabis found as well as on alleged immigration offences.

The UK Border Agency said yesterday that Difhema, an Albanian, was an illegal immigrant and was taken to the Yarl’s Wood Immigration Centre in Bedford to await deportation.

The man was letting the detached house from the Dereham-based agency Pelorus for £800 a month, for the past six months, with his family.

Steve Webster, from the company, said the EDP report on the police operation was the first he had heard of any problems at the house, and added he was shocked at the news.

The incident in Watton comes as Crimestoppers launch today a campaign to help people recognise the smell of cannabis and report suspected plantations.

They say there has been a 15pc rise in the number of cannabis farms found in homes between 2011 and 2012.

Marijuana-scented scratch cards are to be posted to hundreds of households in a bid to detect illegal cannabis farms.

Sgt Gareth Woodward, from Norfolk police, said: “This was a proper cannabis factory set-up and not just run of the mill.”

He added: “This is very good news for the local community and we are always very keen to get information on anyone dealing or growing drugs. I would urge anyone with any information about this sort of thing happening in their local community to contact Norfolk police or Crimestoppers.”

Norfolk police can be contacted on the non-emergency 101 number and Crimestoppers can be called on 0800 555111.